QuEChERS结合气相色谱三重四极杆串联质谱法测定高粱中45种农药残留

该实验建立气相色谱三重四极杆串联质谱法（GC-MS/MS）结合改良的QuEChERS方法同时检测高粱中45种农药残留。高粱粉末加水浸润后，加入10 mL乙腈-乙酸乙酯（1∶1，V/V）溶液，加入WondaPak提取盐试剂包Ⅱ提取，取上清液加入WondaPak净化管Ⅲ净化，氮吹近干，定容至1 mL，基质内标法定量。在质量浓度为0.05～1.00 μg/mL范围内，各农药的线性关系良好，线性回归方程的相关系数（R2）均＞0.995，方法检出限为0.001 2～0.042 4 mg/kg。分别向阴性高粱样品中添加质量浓度为0.01 mg/kg、0.10 mg/kg和0.50 mg/kg的45种农药标准品，其平均加标回收率为76.32%～108.45%，精密度实验结果的相对标准偏差（RSD）为0.12%～10.95%。与其他农药残留检测方法比较，该方法具有前处理操作简单、重复性好、灵敏度高、降低分析成本等优势，适用于高粱样品中农药的高灵敏度快速检测。

Determination of 45 pesticide residues in sorghum by QuEChERS combined with gas chromatography triple quadrupole tandem mass spectrometry

A gas chromatography triple quadrupole tandem mass spectrometry (GC-MS/MS) method combined with an improved QuEChERS method was established for the simultaneous detection of 45 pesticide residues in sorghum. After the sorghum powder was soaked in water, 10 ml acetonitrile- ethyl acetate (1∶1, V/V) solution and the WondaPak extraction salt reagent pack II were added for extraction, the WondaPak purification tube III was added to supernatant for purification, the nitrogen was blown to nearly dry, the volume was fixed to 1 ml, and the matrix internal standard method was used for quantification. In the mass concentration range of 0.05-1.00 μg/ml, the linear relationship of each pesticide was good, the correlation coefficient (R2) of the linear regression equations were all greater than 0.995, and the detection limit of the method was 0.001 2-0.042 4 mg/kg. Adding 45 pesticide standards to the negative sorghum samples at three levels of 0.01 mg/kg, 0.10 mg/kg and 0.50 mg/kg, the average standard recovery rate was 76.32%-108.45%, and the relative standard deviation (RSD) of precision test results was 0.12%-10.95%. Compared with other pesticide residue detection methods, the method had the advantages of simple pre-processing operation, good repeatability, high sensitivity, and reduced analysis cost, which was suitable for high-sensitivity and rapid detection of pesticides in sorghum samples.